Street lighting luminaire



Jan. 24, 1956 w. B. ELMER STREET LIGHTING LUMINAIRE 5 Sheets-Sheet 1 Filed Feb. 24, 1953 Jan. 24, 1956 w. B. ELMER STREET LIGHTING LUMINAIRE 5 Sheets-Sheet 2 Filed Feb. 24, 1953 1956 w. B. ELMER 2,732,483

STREET LIGHTING LUMINAIRE Filed Feb. 24, 1953 5 Sheets-Sheet 3 Jan. 24, 1956 Filed Feb. 24, 1953 W. B. ELMER STREET LIGHTING LUMINAIRE 5 Sheets-Sheet 4 1956 w. B. ELMER STREET LIGHTING LUMINAIRE 5 Sheets-Sheet 5 Filed Feb. 24. 1953 United ates. P t n 0.

I 2,732,483 7 STREETLIGHTING L m AmE William B. Elmer, Boston, Mass. Application February 24, '1953, Serial No. 338,538

4 Claims. (Cl. 240-2 5 This invention relates to street lighting-laminates.

One object of the invention is to provide a street lighting luminaire adapted to use fluorescent lamps. An advantage of a fluorescent lamp is that it provides a large luminous area at the light source and haslowsurface brightness thereby reducing the glare caused by most street lighting units now in common use.

One characteristic of a fluorescent lamp is that itsefficiency is reduced when it is operating in a very cold atmosphere. Accordingly another object of the invention is to provide a street lighting luminaire using fluorescent lamps which is equipped with means for'supplying heat to the atmosphere in which the fluorescent lamps .are located, thereby maintaining'their efliciency even in very cold weather.

Another object of the invention is toprovide a street lighting luminaire using fluorescentlamps which is inexpensive to manufacture, which is not excessively large or heavy, and which does not present an especially ungainly appearance.

Referring now to the drawings, wherein I have illus-. trated a selected embodiment of my invention,

Fig. 1 is a side view of a street lighting'1uminaire embodying my invention. H i

Fig. 2 is a rear end view thereof right of Fig. 1.

Fig. 3 is a front end viewlooking .toward the left, Fig. 1. 3

Fig. 4 is a top plan view.

Fig. 5 is a section on the line,55, Fig. 1

Fig. 6 is a section on the line 6-6, Fig. 3.

Fig. 7 is a view of the sheet metal blank which is used in making the upper section of the rear 'end element.

Fig. 8 shows the manner inwhich said upper'section is fashioned from the blank showninFig. 7."

Fig. 9 is an enlarged fragmentary view of the retaining strip. I

Fig. 10 is a section on the line l-1 0,Fig. 2.

Fig. 11 is a section on the line 11 11, Fig. 3.

The luminaire embodying my invention presents a housing to receive the fluorescent lamps and which is formed by a top element 1, a front end element 2, a rear end element 3, a bottom element 4, andtwo trapezoidalpanels and 6 which are made of some light transmitting material, such as glassor Plexiglas. Thetop element, and elements, and bottom. element aresecured together to form a skeleton'supporting frame in which the light transmitting side panels 5 and 6 are supported.

The side panels are so mounted .in the skeleton frame that they incline toward each other from the top "to the bottom and also incline toward each other from the rear end member 3 toward the front end member 2."

.These elements thus forrnthe walls of 'a chamber in which the fluorescent lamps Tare located, said chamber being widcr at the top 'than'at the bottom, and wider at.

looking toward the the rear endthan at the front end j a The top element land theendfqlemen'ts 2'and'3 and bottom element 4' are made of sheetmaterial havinga highly reflecting interior surface such as would be provided by making these elements with an inner surface of white porcelain enamel.

The top element 1 is wider .at its rear end than at the front end, and is provided with two'downwardly opening grooves 8 and 9 in which the upper edges of the light transmitting panels 5 and 6 are received. These grooves are well spaced from the edges of the top element and converge ,toward each other from the rear to the front, said grooves being very nearly parallel to the side edges of the top element.

The rear end member 3 is also wider at the top than at the bottom and is provided with two open grooves Ill) and 11 in which the rear edges of the panels 5 and 6 are received. These grooves 10 and 11 converge toward each other from the top to thebottom, and at the bottom the two grooves are spaced apart a distance corresponding to the width of the bottom element. The front end element is provided with open grooves 12 in which the front end of the panels 5 and 6 are received, said grooves also converging from the top to the bottom and being parellel to the grooves 10 and 11. The rearend element 3 is longer than the front end element 2, and the bottom ends of the two end elements have substantially the same width. The bottom element inclines upwardly from the rear end element to the front end element and has a substantially uniform width.

. The bottom edge of each side panel 5 and 6 is received in a bottom groove 13 with which the bottom member 4 is provided. Said member 4 has a channel shape, as shown in Fig. 5, and the lips 14 of said bottom member provide the inside walls of the grooves 13. The outside wall of said grooves is provided by a strip 15 which is detachably secured to the corresponding lip 14 by means of screws 16.

With this arrangement the strips 15 may be removed andthe two panels 5 and 6 slipped into place with the top edges occupying the grooves 8 and 9 and the end edges occupying the grooves in the front and rear elements 3 and 4. After the panels 5 and 6 have been installed the retaining strips 15 may be secured to the lips 14 of the bottom member 4 thereby firmly holding the side panels in place.

The front end element has mounted thereon a plural socket member 17 carrying sockets 18 to receive the fluorescent lamps 7 and the rear end member 3 also has tion 21 is preferably formed from a sheet metal blank mounted thereon a plurality of sockets 20 to receive the other end of the fluorescent lamps 7.

The'rear end element 3 is made in two sections, an upper section 21, and a lower section 22. The upper sec- 23'of the shape shown in Fig. 7. This blank is provided with two parallel cuts 24 and two lateral cuts 24a and thereafter the blank is bent along the dotted lines 25, so that the sections 26 stand at right angles to the central section 27 and the blank is then again bent in the opposite direction along dotted lines 28 to provide the wing sections 29. The portion 30 between the cuts 24 is then bent inwardly, as shown in Fig. 8, and suitably welded to the bottom of the sections 26.

Bythus fashioning the blank the edges of the cuts 24 are brought together, as indicated at 31, said edges being suitably secured together, as by welding. This provides an upper section 21 which presents two flat wings 29 and a rearwardly projecting chamber formed by the sections 26 and 27.

The lower edge of the finished section 21 is bent into the U-shape 37, as shown in Fig' 8.

' The lower section 22 is made'from a suitably shaped piece of sheet metal which is cut away to provide a door opening 38 to provide access 'to the fluorescent lamps 7,

at its upper end' tothe upper section 21* by suitable" hinges 62.

The top element 1 is deformed. to present a down.- wardly facing ch'anuel40" which extends the full'length' thereof and which is adapted to receive the usualballast elements 41 for the fluorescent lamps. the channel itlis closed by a sheet metal strip. 42, the. edges of which are welded or otherwise. securedto the side walls of the channel;

The top element and'end elements may be secured to gether in any suitable way. As herein shown the end elements are provided with wings or tabs. 44 adapted. to be folded under the top of the top element and either riveted or welded thereto. The. bottom element 4 is also shown as having at each end an upturned tab 45ad'apted to be welded'or rivetedto the bottoms of the endmembers.

The lnmiuaire may be mounted on a pole 46' in any suitable way. As herein shown said pole has a bracket arm 47 suitably secured thereto, the outer endofwhich' extends through an opening 59 formed'in the upper sec tion 2 of the rear end'member 3' and'occupies the outer portion of the channelit The end" of the arm' is'clamped" by U-bolts 48 to theplate 42, asbest seen in'Fig; 6.

Vith the above construction the fluorescent lamps 7 are situated directly behind the sidepanels and 6 and since the light transmitted through a fiat light-transmitting panel is greatest in a direction perpendicular to the panel and since the fluorescent being shown arranged one above the other, present a substantially flat diffusing light source, the" maximum light which is transmittedthrough the panels will be'a' broad beam extending at right angles to the panels; These panels are inclined to the vertical, as shown= in Fig. 5, and hence the strongest light beams which, as stated above; extend atright angles to the panels; will have adownwardly inclined direction; Furthermore,

since these panels are inclined toward each other from" the back to the front of the luminaire, the beam-of light will have a slight angle to'the length of thestreet which is important where the luminaire is mounted on a pole at the side of the street. The desired light distribution for illuminating a street is therefore obtained without the use of supplementary internal reflectorsother than the interior reflecting surfacesof the-housing:

The invention also includes means for heating the' chamber within the housing in which the fluorescent lamps 7 are located thereby to maintain theefiicieucy of such lamps even in very cold weather. For this purposei have provided a heating element in the form of a mercury lamp 49 which is installed inthe chamber at the rear end thereof above thelower'ends'of the' fluorescent lamps 7. The ballast 50, which is: required for operating a mercury lamp, is'shown as'being housed in the chamber with which the upper section 21 of therear and member is provided. This mercury'lamp' serves-not only to maintain a proper operating temperature. within the housing in cold weather, but it also contributes a substantial amount of light to theeuclosureand to the:

portion of the chamberwhich otherwise wouldhave been the darkest region.

The door 39 is: shownasiprovided. with a hooked rod. 51, the end of which can;behooked'into. an eyeaboltt52. for holding, the door openwhile an operator is inspecting the interior of the lumiuaire, or is removing or replacing fluorescent lamps.

For locking the door closed there is provided. a. screw threaded stud 53 which. is received in a slot 54 formed. in the bottom of the door when the latter. is closed and. on which is screwed a lockingnut 55.by means of which the door is locked inits. closedpositiom It has been stated that. the grooves. 8 and. 9 on. the under side of the top element are: wellspacedfromthe. edges of said eiement and also. converge toward. each The bottom of lamps 7, four such lamps thetop*elerrrent prcsents*twc-side"edge-portions 64whichextend beyond the panels Stand 6. The top element is constructed so that the two sides thereof incline down wardly slightly from the center line toward the edges and, as previously stated, the under surface of the top element has a highly reflecting characteristic. The edge portions 64 of the top elementwhich are outside of the grooves 8 and.9 thus.constitute.reflecting vizor portions by which any light'rays from the fluorescent lamps which strike the vizor; portions: will: be. reflected downwardly onto the street, thus. supplementing the. lighting effect produced by'the light rays that are transmitted direcly from the fiuorescentJamps.through; the. side panels.

It may be noted that the grooves 10 and 11 in the rear end member are also well spaced from the side edges of said member so that said end member presents two edge portions 65 which. extend. beyond the rear endsv of thesidepauels' S and 61 These edge portions 65, which the wider at thetop than at the bottom, constitute shieldiirg'portionsewhiclr serve to shield the'buildings on the side: of the strcet'from thedirect light rays emanating from the. fluorescent lamps;

I claim:

1. A street lightiiig'lurninaire comprising a housing having ahoriiontally=disposed top element whichis wider ari'ts rear end.than'at'its"front end; a vertically disposed rear end element which is wider at its top than at its bottom; a vertically disposed front end element which is alsowider-fiat itstop than at its bottom, said rear end element beinglonger than the front end' element, both end elements haviug'the same width at the bottom, a bottom element connecting the bottom edges of the two end-elements, saidbottoru'elernent having a substantially uniform width which corresponds to the width of the endelements attheir bottom ends; said top element having onits underface two panel-receiving grooves, one on each side, of its medial line, said grooves converging toward each other from" the' rear to the front, each end element having" on its inner face two panel-receiving whichthe under.- face of the top element has high light' reflecting characteristics and. in. which the panel-receiving grooves on the under. side. thereof are Well spaced from the side edges of the top element and extend outwardly beyond the side panels, such extending portions of the top element constituting reflectingvizor sections which reflectlight from-thefluorescent'lamps downwardly onto the street.

3; A.street lighting luminaire as defined in claim 1 in which. the. grooveson the. inner. face of the rear end element. converge'toward: each other from the top to the bottomand are well spaced' from-theside edges of said endelemene whereby the edge portions of the rear end elements extend beyond' the side panels and constitute shielding sectionswhich' shield dwellings on the side of the street from direct illumination by the fluorescent lamps:

4. A streetli'ghtingluminaire as defined in claim 1 in whichthe bottom element has upturned side edges against the. outsideof whichthelower edges of the side panels rest and each said. side panelv is retained in its grooves by a retaining strip which. has its lower edge portion overlying and. detachably secured. to the. corresponding upturnedllip; ofithe. bottom member and has its upper edge portion oifset from its lower edge portion and overlying the outside lower edge of the panel.

References Cited in the file of this patent UNITED STATES PATENTS 6 FOREIGN PATENTS Great Britain Sept. 10, 1934 France June 20, 1951 Austria Dec. 27, 1951 

